The influence of obesity on the remission of rheumatoid arthritis treated with methotrexate

Abstract

Background. Obesity remains a factor that negatively influences patients with rheumatoid arthritis (RA) amplifying inflammation and reducing the effectiveness of Background. methotrexate treatment. Thus, it increases the risk of remission failure and may affect the evolution and long-term prognosis of the disease. Objective(s). Determining the risk of remission failure in patients diagnosed with rheumatoid arthritis treated with methotrexate (MTX) monotherapy, with obesity taking into account comorbidities. Materials and methods. The study included 86 patients with RA (56 women, 30 men) diagnosed according to ACR/EULAR 2010 criteria, mean age 47±0.8 years, disease duration 51.5±5.0 months, treated with MTX. Patients were divided according to BMI: normal weight (18.5–24.9), overweight (25–29.9) and obese (≥30). Remission was assessed at 6 and 12 months according to DAS28. Results. Of the total group of patients, 18% had a BMI >30. At 6 months, 59% of obese patients did not achieve remission according to the DAS28 score, compared with 48% of those with normal BMI. At 12 months, remission rates were 62% vs. 44%. Obesity was associated with an increased risk of failure of clinical remission at 6 months (RR=1.23) and 12 months (RR=1.41), after adjustment for comorbidities. This association was more pronounced in women and in those with smoking status. Similarly, obesity was linked to increased values of inflammatory markers and higher subjective perception of pain, but not to persistent joint inflammation. Conclusion(s). Obesity is an independent risk factor that significantly increases the chances of failure of remission in rheumatoid arthritis patients treated with methotrexate, by accentuating the inflammatory status, this effect remaining regardless of the presence of other associated comorbidities.